The Cooperating Clinics Committee (CCC) of the American Rheumatism Association has, since 1958, developed a mechanism for the study of drug effects on rheumatoid arthritis, and proposes to continue and expand this work. Program objectives are: 1. Because of the large number of non steroid antiinflamatory agents which have become available in the past two years, we propose rapid, efficient methods of screening drugs in small clinical trails, in order to select the most promising for more extensive trials. 2. To conduct multi-center, rigorously controlled trials of anti-rheumatic drugs by sequences of trials, which ill optimally allocate patients to the best drug available. 3. To study the methods of clinical and laboratory assessment of patients' disease status with respect to their validity, reproducibility, and inter-relationships, and to develop better methods of assessment, record keeping, and data retrieval in chronic rheumatic disease. 4. To study natural histoty of rheumatoid arthritis and other connective tissue disease, in a search for possible patterns of signs, symptoms or laboratory results which would allow the identification of distinct species within the genus now labeled "rheumatoid arthritis;" and/or which might give prognostic information; and/or which might suggest the need for distinct and different therapies for discrete subgroups. 5. To develop, encourage, and assist the various clinics in undertaken smaller, individual pilot trials and investigations which might subsequently require the resources of the entire group.